So, it is a known and acknowledged fact that Nightblade's Shadow Cloak skill and its morphs Dark Cloak and Shadowy Disguise have had a number of long-standing bugs.
A small handful of bugs have been fixed, which is great.

Unfortunately, a number of bugs still remain.
In particular,
@ZOS_JessicaFolsom posted about a couple of them on May 22nd, 2014.
Incoming Fixes & Improvements
...
Outstanding Known Issues
Patch 1.1.2 fixed many outstanding Nightblade issues, but below are some that we are either actively investigating, working on fixes for now, or have recently fixed and will push in a future patch. Please note this list does not reflect every reported Nightblade issue we are currently investigating.
General: Currently, a Nightblade’s own residual outgoing damage-over-time ticks break his or her invisibility. This is not intended, and will be fixed in a future patch.
Dark Cloak (Shadow Cloak morph): Dark Cloak is not currently removing damage-over-time (DoT) debuffs as it should be. We’re currently investigating this issue to determine which DoTs are not being removed by Dark Cloak.
...
Thread available here:
http://forums.elderscrollsonline.com/discussion/100627/nightblade-update/p1
Since May 22nd, there have been no further updates with regards to progress on these long-standing bugs.
Can we get an update on these acknowledged unintended bugs?
Will we be seeing a fix for them soon, such as in 1.4?
Will the fix still take longer than that? If so, can we get a time-frame and information as to why?
Is the bug team making any progress on these issues? Do they need more information from players?
I'd be willing to compile a list of DoT skills that are adversely impacting Shadow Cloak if that is necessary to seeing these bugs get fixed.
In their current incarnation these bugs are having an adverse effect on players and still need to be fixed.
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